“Mars can be very deceptive,” said Chris Roumeliotis, Curiosity’s lead rover driver at NASA’s Jet Propulsion Laboratory.
Earlier this month, the rover had trouble tackling slopes with sand ripples on it. In the past, Curiosity slipped on a similar surface. Curiosity’s mission team knew this and decided to try and drive around the ripples on what appeared to be a rockier surface with “more consolidated characteristics directly adjacent to these ripples,” said Roumeliotis.
“Unfortunately, this terrain turned out to be unconsolidated material too, which definitely surprised us and Curiosity,” he said.
The rover had issues on three out of four drives.
A view of the terrain deemed too difficult to traverse. You can see the sand ripples in the bottom middle and bottom left of the image.
Curiosity was headed south of a feature called ‘Jocko Butte’ to another geological feature in the eastern part of the ‘Logan Pass’ area.
Mission controllers decided it was best to head back to Jocko Butte and figure out an alternative route.
The team spent several days looking at images from the rover and NASA’s Mars Reconnaissance Orbiter to find the best route for the rover mission.
“One factor the science team considers is how much time to spend reaching a particular target, when there are many others ahead,” said Curiosity Project Scientist Ashwin Vasavada of JPL.
“We used observations from NASA’s Mars Reconnaissance Orbiter to identify an alternative site for investigating the geological contact in the Logan Pass area. It’s a little mind-blowing to drive up a hill to a site we saw only in satellite images and then find it in front of us.”
Last Thursday, Curiosity drove 72 feet up the hill with slopes as steep as 21 degrees to the new target area.
Geological contacts are where pale rocks meet dark overlying rocks. They can reveal clues about how environmental conditions that produced dark rocks were related to conditions that produced white rocks.
The middle portion of the image below shows a geological contact.
After Curiosity finishes examining this area, it will continue its trek up Mount Sharp.
Image credits: NASA